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table of differences between and for
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(Data Structure)
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There are only three known solutions to Brocard's problem, and the near misses all seem to occur early on. Notice how, for example, 3! is just 3 shy of a square (compared to 1 shy of a square which is what Brocard's problem asks for). Still, the differences between a factorial and the next higher perfect square don't make
for a consistently ascending order sequence. For a few values of , (such as 4, 7, 10, 24, 26, 42, 117, 135) this difference is smaller than the previous difference. In general, however, the difference between a factorial and the next perfect square widens as gets larger.
The following table gives the square root of to six decimal places, and then the difference between the factorial and the next higher square (obtained by taking the ceiling of the square root of and squaring that integer).
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| 1 |
1.000000 |
0 |
| 2 |
1.414214 |
2 |
| 3 |
2.449489 |
3 |
| 4 |
4.898979 |
1 |
| 5 |
10.954451 |
1 |
| 6 |
26.832816 |
9 |
| 7 |
70.992957 |
1 |
| 8 |
200.798406 |
81 |
| 9 |
602.395219 |
729 |
| 10 |
1904.940944 |
225 |
| 11 |
6317.974359 |
324 |
| 12 |
21886.105181 |
39169 |
| 13 |
78911.474451 |
82944 |
| 14 |
295259.701280 |
176400 |
| 15 |
1143535.905864 |
215296 |
| 16 |
4574143.623456 |
3444736 |
| 17 |
18859677.306253 |
26167684 |
| 18 |
80014834.285449 |
114349225 |
| 19 |
348776576.634429 |
255004929 |
| 20 |
1559776268.628498 |
1158920361 |
| 21 |
7147792818.185865 |
11638526761 |
| 22 |
33526120082.371712 |
42128246889 |
| 23 |
160785623545.405884 |
191052974116 |
| 24 |
787685471322.938354 |
97216010329 |
| 25 |
3938427356614.691406 |
2430400258225 |
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"table of differences between and for " is owned by PrimeFan.
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(view preamble)
Cross-references: integer, square root of 3, ceiling, decimal places, square root of 2, sequence, ascending order, perfect square, factorial, differences, square, near, Brocard's problem, solutions
This is version 2 of table of differences between and for , born on 2008-07-01, modified 2008-07-02.
Object id is 10735, canonical name is TableOfDifferencesBetweenLceilSqrtnRceil2AndNFor0N26.
Accessed 170 times total.
Classification:
| AMS MSC: | 11A25 (Number theory :: Elementary number theory :: Arithmetic functions; related numbers; inversion formulas) |
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Pending Errata and Addenda
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